package com.wuxiaofan.config;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.netty.buffer.ByteBufAllocator;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.InetSocketAddress;
import java.net.URI;
import java.nio.charset.StandardCharsets;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.core.io.buffer.NettyDataBufferFactory;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StreamUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

/**
 * @author wuxiaofan
 * @date 2021/7/23 5:38 下午
 */
@Slf4j
@Component
public class AccessLogGlobalFilter implements GlobalFilter, Ordered {

    private final ObjectMapper mapper = new ObjectMapper();
    private final DataBufferFactory dataBufferFactory = new NettyDataBufferFactory(ByteBufAllocator.DEFAULT);

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();

        String method = request.getMethodValue();
        String contentType = request.getHeaders().getFirst("Content-Type");
        log.info("请求地址:{},",request.getPath().pathWithinApplication());
        log.info("请求方式:{},请求参数类型:{},",method,contentType);
        if ("POST".equals(method)) {
            return DataBufferUtils.join(exchange.getRequest().getBody())
                    .flatMap(dataBuffer -> {
                        byte[] bytes = new byte[dataBuffer.readableByteCount()];
                        dataBuffer.read(bytes);
                        try {
                            String bodyString = new String(bytes, "utf-8");
                            log.info("请求参数:{}",bodyString);//打印请求参数
                            exchange.getAttributes().put("POST_BODY", bodyString);
                        } catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                        DataBufferUtils.release(dataBuffer);
                        Flux<DataBuffer> cachedFlux = Flux.defer(() -> {
                            DataBuffer buffer = exchange.getResponse().bufferFactory()
                                    .wrap(bytes);
                            return Mono.just(buffer);
                        });

                        ServerHttpRequest mutatedRequest = new ServerHttpRequestDecorator(
                                exchange.getRequest()) {
                            @Override
                            public Flux<DataBuffer> getBody() {
                                return cachedFlux;
                            }
                        };
                        return chain.filter(exchange.mutate().request(mutatedRequest)
                                .build());
                    });
        }
        return chain.filter(exchange);
    }

    @Override
    public int getOrder() {
        return 0;
    }
}
